The ____ is an exchange organ formed by material and fetal tissues, and represents an effective barrier against most microorganisms in the maternal circulation
Fill in the blank(s) with the appropriate word(s).
placenta
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Budding is a form of reproduction whereby prokaryotic microbes can reproduce sexually
Indicate whether the statement is true or false.
Your descendants have fortunately inherited your fascination with rodent genetics
Fifty thousand years after the original volcanic eruption (a vicariance, or vicariant event), your descendants return to the island and repeat the same sampling and DNA sequencing strategy. DNA SEQUENCE TABLE * * * * * * * * * * * * AACGT TCGAT GCCTT AGCCC TGACT ATGGT CAGTA CGTAC TTCGC Above is a sequence of the mtDNA region analyzed. The 12 stars mark the 12 nucleotide sites that vary among the individuals sequenced. Note that most of the nucleotide sites are the same across all individuals sampled. In presenting the sequences of five randomly selected individuals below, we show only the base pairs at each of the 12 variable sites. Initial population, before the volcanic eruption Population A T=0 1. AATGCCGGACGT 2. AAAGGCGGACGT 3. AATGGCGGACGT 4. AATGCCGGTCGT 5. AAAGCCGGACGT T=0 after vicariant event Population A1 Population A2 1. AATGCCGGACGT 1. AATGCCGGACGT 2. AAAGGCGGACGT 2. AAAGGCGGACGT 3. AATGGCGGACGT 3. AATGGCGGACGT 4. AATGCCGGTCGT 4. AATGCCGGTCGT 5. AAAGCCGGACGT 5. AAAGCCGGACGT T = 50,000 years after the vicariant event Two fixed differences between A1 and A2 1. AATGCCGGACGA 1. AATGCCGGCCGT 2. AAAGGCGGACGA 2. AAAGGCGGCCGT 3. AATGGCGGACGA 3. AATGGCGGCCGT 4. AATGCCGGTCGA 4. AATGCCGGCCGT 5. AAAGCCGGACGA 5. AAAGCCGGCCGT T = 100,000 years after the vicariant event Four fixed differences between A1 and A2 1. AATGCCGGACGA 1. AATGGCGGTCGT 2. AAAGCCGGACGA 2. AAAGGCGGTCGT 3. AATGCCGGACGA 3. AATGGCGGTCGT 4. AATGCCGGACGA 4. AATGGCGGTCGT 5. AAAGCCGGACGA 5. AAAGGCGGTCGT ***If you have population sequence data from an actual gene this could also be used to talk about specific mutation patterns in that specific gene. Alternatively you could also supply SNP data over time to help students better understand different types of markers used with many genomic level studies. This decision is up to the instructor. Many don't discuss SNP data in their course, so the example could be used as is. Their data indicate there is no reproductive isolation between members of A1 and A2. Compare the DNA sequences presented above and give the amount of variation expected: ...between two randomly chosen individuals of A2. A. relatively low variation B. moderate variation C. relatively high variation
The technique of deletion analysis revealed the modular architecture of Gal4p. In deletion analysis, nucleases or restrictionenzymes are used to selectively:
A. delete pieces of DNA froma specified gene. B. remove truncated protein products of a gene. C. restore in vitro activity of proteins to mutant cells. D. activate genes in vivo using a reporter assay.
If short hair (L) is dominant to long hair (l), then to
determine the genotype of a short-haired animal it should be crossed with a. LL. b. Ll. c. ll. d. all of these. e. none of these.